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Volume 25, Issue 9
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Observation for Automatic Welding Procedure of Structural Steel of Large ThicknessT. Yoshida, W. Matsunaga, K. Terai1956 Volume 25 Issue 9 Pages 486-492
Published: September 25, 1956
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSIt has been disturbing experience of those engaged in submarged arc welding of structural steel plates to find cracks in the weld metal. These cracks which frequently take place while the weld is still very hot, and usually while the joint is subjected to high stresses, are associated with weakness between dendrites and it is believed to be probably hot cracking caused by increasing restraint due to the larger thickness of plates.
Using large restraint specimens authors have experimented of the development of these cracks quantitatively and compared the various welding procedures with the result obtained.
Covering the experimental methods used and the results obtained, this paper presents data whose several phases are as follows :
(1) In order to prevent the restrained crack, it is more desirable the deposit of the first layer is made larger. (cf Fig. 5, 6 and 7)
Generally, speaking of the performance of joint after welded, a multi-layer weld is said better. However, in view of such fact, it seems to be somewhat dangerous to increase the number of layers too much, which may cause the dwindling of the deposit of the first layer.
(2) Among two combinations of rod and flux used in test, the low manganese rod of the combination I whose width of bead is larger is showing much better result (cf Fig. 5, 6, 10 and 11) As for the restraint crack of manual welding, better fusion and higher the deposit top is showing a better result, but a different aspect is presented in the automatic welding.
(3) In the restraint crack of manual welding, the cold crack mainly poses a problem, but in the automatic welding it is conceivable the crack develops at a fairly high temperature (cf Fig. 10, 11).View full abstractDownload PDF (11485K) -
Homageneous Thermal Distribution in ArcT. Ohwa1956 Volume 25 Issue 9 Pages 492-497
Published: September 25, 1956
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSThe equation of temperature-distribution in the quasi-static state was derived assuming the heatsource of circular shape. The shape of penetration decided by the equation is similar to ellipse. It seems to be proper to set the heat-efficiency about 80%.View full abstractDownload PDF (2182K) -
Weldability of Semi-Killed Steel PlateT. Ohwa1956 Volume 25 Issue 9 Pages 497-502
Published: September 25, 1956
Released on J-STAGE: December 10, 2009
JOURNAL FREE ACCESSDirectionality, sensitivities for the straining and heat-treatment, influence of hydrogen for the weldability of semi-killed steel plate were investigated, using some kinds of arc-welding covered electrodes, those produce the weld metals with different contents of hydrogen. Hydrogen, which transfered from weld-metal to heat-affected zone (H.A.Z.), increases the max. hardness and decreases toughness of H.A.Z., further, promotes the accurence of under-bead-crack, which mainly caused by the laminar segregation in the steel plate. min. toughness of H.A.Z. were recognized in the neighbour of bond, A1 and A1+3mm.View full abstractDownload PDF (5803K) -
Shrinkage Distortion in Welded Joints (Report 4)M. Watanabe, K. Satoh1956 Volume 25 Issue 9 Pages 502-506
Published: September 25, 1956
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSChange of root opening during butt-welding is effected by welding conditons and by the constraint of joint. Two types of ring specimen as shown in Fig. 1 are used, and the following experiments are done :
Case 1 ...... Specimen α, Weld AC (weld of first pass of free butt-joint)
Case 2 ...... Specimen b, Bead weld AC
Case 3 ...... Specimen α, Weld DB
The change of root opening is meaursed by dial gauge at the point B (see Fig. 1). The results of Case 2 are shown in Figs. 2-5., the results of Case 1 in Figs. 6 and 7 and the results of Case 3 in Fig. 8. Difference in manual weld and submerged arc weld is observed in Case 1.View full abstractDownload PDF (357K) -
I. Onishi, T. Okui1956 Volume 25 Issue 9 Pages 506-511
Published: September 25, 1956
Released on J-STAGE: December 10, 2009
JOURNAL FREE ACCESSPhosphor deoxidized copper and also tough pitch copper plates of 3-4mm thickness were butt welded with nitrogen-arc welding process. Welding conditions such as nitrogen flow, welding current, arc length and travelling speed were selected properly, Good weld result was obtained only when silicon deoxidized copper was used as a filler rod.View full abstractDownload PDF (4328K) -
K. Yokota, S. Eto1956 Volume 25 Issue 9 Pages 512-516
Published: September 25, 1956
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSIf a construction made of steel plates is used instead of a casting, many ribs must be welded to the body in order to reinforce the construction.
Such a case like this, it is necessary to check the influence of the stresses caused by the welding. However, only a few experiments or calculation were made on this subject and also, it was seldom that the reports available to refer. With the aim to contribute this study to facilities for designing of such a construction, the influence of the welded ribs on the static and impact bending stresses was studied by a simple body. This body was constructed by welding ribs on a steel plate having a rectangular section. The stress distribution was measured by a resistance strain gauge.View full abstractDownload PDF (3384K) -
Behaviors of Over-Strained MetalsM. Watanabe, S. Goda, M. Hayasi1956 Volume 25 Issue 9 Pages 517-521
Published: September 25, 1956
Released on J-STAGE: December 10, 2009
JOURNAL FREE ACCESSThe authors had reported the transition phenomenon of the increasing creep rate with the augment of prestrain, in the torsional creep test of previously twisted mild steel. In this report, we investigated the same phenomenon in the torsional creep test to HCM steel previously tensioned.
From. Figs. 6-8, We know that, on increasing the prestrain of the steel, creep rate increases abruptly, after the prestrain exceeds the ultimate-point, to about two times of creep rate before that point and appears to remain constant approximately before and after this transition zone.
Fig. 9 shows the relation between strain rate γ (as to γ1 and γ2, see Fig. 6-8) and the value of stress τ ; on the while, Fig. 10 shows the experimental results concerning the following relation,
{ γ=KPn
P=γ⋅e- /RT,
where K and n are the constants, T is the absolute temperature, Q is the activation energy and R is the gas constant. From these relations, we know that the ratio γ2/γ1 is constant (about1/2) independently of the value of shear stress.View full abstractDownload PDF (347K) -
Welding Conditions, Penetration and Black PowderH. Suzuki, T. Murase1956 Volume 25 Issue 9 Pages 521-526
Published: September 25, 1956
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSVarious tests oh the inert-gas metal-arc welding of a corrosion resisting aluminum-magnesium-manganese alloy "ANP", have been performed with ANP-O and ANP-1/4H plates, 1/4in. in thickness, and various consumable electrode wires, 2S, 52S, A54S, 56S and ANP. The tests consisted of, (1) effect of welding condition on penetration and bead shape, (2) influence of surface treatment, welding condition and technique on occurence of black powder arround bead and porosities in weld metal, (3) cracking properties versus filler wires, (4) mechanical properties of butt welded joint, (5) ductility and mode of fracture in tensile test, (6) hardness distribution and weld thermal cycle in welded joint, (7) effect of weld porosities on mechanical properties of butt joint, (8) microstructure, and (9) corrosion of welded joint.
The present report Part 1 includes the tests (1) and a half of (2). The penetration characteristics, electrode melting rate and the effects of welding conbitions, filler wires, surface treatments, and torch angle on the occurence of black powder are discussed.View full abstractDownload PDF (6305K) -
[in Japanese]1956 Volume 25 Issue 9 Pages 527-531
Published: September 25, 1956
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSDownload PDF (3616K) -
[in Japanese], [in Japanese]1956 Volume 25 Issue 9 Pages 532-538
Published: September 25, 1956
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSDownload PDF (5747K)
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